Microgravity

• Messages sorted by: [ date ][ thread ][ subject ][ author ]
• Next message: Bjorn Gimle: "Sv: ERBS observation"
• Previous message: Ted Molczan: "RE: STS-73 'beam' observation"

                                              

Jeff Hunt asked why the term "microgravity" instead of "zero gravity."

Zero gravity implies the complete absence of gravity waves.  This occurs
nowhere in the known universe - not even in deep space.

An object in orbit seems to be at zero gravity because the centrifugal force of
the object describing an elliptical or circular path cancels out the force of
Earth's gravity.  But there are other gravity forces that are not cancelled
out, such as that of the Sun, Moon, an astronaut five feet away.  Also, the
Earth's mass is not distributed uniformly.  All of this adds up to minor
perturbations, and thus "microgravity."
                                            
 -- Jim


+------------------------------------------------------------------------+
Jim Varney, P.E.                                           Sacramento, CA
Civil Engineer                                      jim.varney@24stex.com
+------------------------------------------------------------------------+

• Next message: Bjorn Gimle: "Sv: ERBS observation"
• Previous message: Ted Molczan: "RE: STS-73 'beam' observation"